Procedure Aof this method covers the measurment of spectral
absorptance, reflectance, and transmittance of materials using
spectrophotometers equipped with integrating spheres. Procedure C
of this method covers the measurement of solar transmittance
(terrestrial) of materials using a pyranometer, and enclosure, and
the sun and sky as the source of radiation.

Methods of computing solar-weighted radiant and luminous
properties from the measured spectral values are specified in
procedures Aand B, which are applicable to materials having both
specular and diffuse optical properties. Except for transmitting
sheet materials that are inhomogeneous, patterned, or corrugated,
proceduresAand B of this method are preferred over procedures C, D,
andE.

Procedure B describes the calculation of luminous (photometric)
transmittance and reflectance of materials from spectral radiant
transmittance and reflectance data, or both, obtained from the
performance ofProcedureAof this method.

Procedure C of this method allows measurement of solar
transmittance of materials in sheet form at normal incidence and at
angles other than normal incidence and is applicable to
transparent, translucent, textured, or patterned sheet
materials.

ProcedureD ofthis method covers the measurement of solar
photometric transmittance of materials in sheet form. Solar
photometric transmittance is measured using a photometer
(illuminance meter) in an enclosure with the sun and sky as the
source of radiation, the enclosure and method of test being
specified in ProcedureC. The purpose ofProcedureDis to specify a
photometric sensor to beused with Procedure C for measuring the
solar photometric transmittance of sheet materials containing
inhomogeneities in their optical properties.

ProcedureEcovers the measurement of the solar radiant and
luminous reflectances at normal incidence, and at other angles, of
sheet materials that are opaque and which may also be textured or
patterned.

PURPOSE

To develop astandard method for measuring and reporting the
following solar optical properties of materials: spectral
transmittance, reflectance, and absorptance between 320nm and 3000
nm in wavelength, and total radiant and luminous transmittance and
reflectance.